The present invention relates to the field of palmtop computers. More particularly, the present invention relates to the selection of input modes for entering alpha-numeric characters on palmtop computers.
The palmtop computer has evolved as a portable device which provides for easy storage, organization, and recollection of information. Palmtop computers are small, compact computers that generally fit in the palm of a person""s hand. The palmtop computer allows for easy operation, as a user simply holds the palmtop computer in one hand (the xe2x80x9cwriting handxe2x80x9d) while entering information with the other hand (the xe2x80x9cnon-writing handxe2x80x9d). Because of the small size of the palmtop computer, the user may simply place the device in a pocket or briefcase when not in use.
When the user wishes to enter information, it is desirable to record the information promptly and accurately. Otherwise, a broad range of problems might occur when the user needs to recall the information. A busy professional might miss an important deadline or meeting. A grocery shopper might buy only a portion of the items needed to prepare a meal.
Conventional palmtop computers generally employ a digitizer pad upon which a user may write with a pen or finger. A handwriting recognition system is generally incorporated to recognize strokes and presses made by the user upon the digitizer pad as individual characters. The handwritten characters are then converted into a machine-readable format such as ASCII code.
One problem associated with conventional palmtop computers has been the poor performance of handwriting recognition systems. Characters input by the user are often improperly identified. For example, a user may attempt to write the number xe2x80x9c1,xe2x80x9d but the letter xe2x80x9c1xe2x80x9d is recognized. Similar, the letter xe2x80x9csxe2x80x9d may be confused for the number xe2x80x9c5.xe2x80x9d When the user recalls what was entered, the palmtop computer returns the erroneous information. The user must then waste time and energy in attempting to ascertain what he originally wrote.
Techniques have been developed to differentiate between characters written on the digitizer pad. One way has been to provide for different xe2x80x9cmodesxe2x80x9d of input. In one embodiment, one mode allows for only lowercase letters to be input (xe2x80x9calpha modexe2x80x9d), a second mode is for only uppercase letters (xe2x80x9ccaps modexe2x80x9d), a third mode is for numbers (xe2x80x9cnumeric modexe2x80x9d), and a fourth mode is for punctuation (xe2x80x9cpunctuation modexe2x80x9d). When input modes are used, the number of possible characters which may be confused for a particular stroke is greatly reduced. For example, if alpha mode is selected, the recognition system will not recognize the letter xe2x80x9csxe2x80x9d as the number xe2x80x9c5.xe2x80x9d Similarly, a lowercase xe2x80x9ccxe2x80x9d will not be recognized as an uppercase xe2x80x9cC.xe2x80x9d
Selecting and switching among various input modes using conventional means takes time and effort on the part of the user. The user must take some action to switch from one mode to another, in addition to the strokes and motions he would otherwise have to make to input the actual characters. For example, some conventional schemes involve the use of xe2x80x9cmode changexe2x80x9d strokes which the user makes on the digitizer pad to change input modes. These mode change strokes must be interspersed with strokes the user ordinarily would make to enter characters. Such systems present various problems. Additional time is required to make the mode change strokes. The mode change strokes themselves are often confused for input characters. Also, it is often not immediately clear to the user which input mode is being used. The particular mode may be displayed on a display area of the digitizer pad, but the user must still look at the device to determine which mode is active.
Thus, conventional methods for input mode selection introduce such discontinuities into the input activity that the quality of interaction is reduced. Users often compromise what is inputted for the ease of inputting it. For example, users may choose not to take the time to capitalize or punctuate when they enter notes because of the time and effort required to change modes. While such informal data entry may be acceptable for personal notes, it may not be acceptable if the user is creating or editing a document that is to be distributed to others.
The present invention relates to a palmtop computer. Characters may be entered using one or more input modes. The computer includes a casing and a digitizer pad coupled to the casing.
According to one aspect of the present invention, the computer includes a physical sensor coupled to select an input mode.
According to another aspect of the present invention, a ridge is formed on the digitizer pad. The ridge is positioned on the pad to define a first input region associated with one input mode and a second input region associated with another input mode.
According to yet another aspect of the present invention, a border is formed around the digitizer pad. The border includes a ridge coupled to select an input mode.
According to yet another aspect of the present invention, the digitizer pad has a first textured region associated with one input mode and a second textured region associated with another input mode.
According to yet another aspect of the present invention, a pen is incorporated. A physical sensor is mounted to the pen and coupled to select an input mode.